Gears??

[00GTpony]

Yea so i have signs by my house that tell u how fast your going.. I just baught my car not to long ago.. and everytime i go past the sign, it tells me im doin 10 mph slower then what my speedometer says. Possible gears in car? or just sumthin else is messed up?

 

[blksgrl]

My speedo was off by about that much after I got mine installed. Guess you could also get a programmer and see if that's it?

 

[goshia]

yep gear change. You can buy a programer and re-calibrate the speedo..

 

[Kilgore Trout]

Put the rear up on jackstands and see how many times the driveshaft fully rotates for one full revolution of the tire...

 

[Nathen4.6]

yep mines off a bit my gps says about 9mph lol which is good cuz if i dont pay attention im going the speed limit.

 

[chevyboy_z28]

mines off by a ton, and unfortunately for me my xcal2 cant recalibarte the speedo on my car, only 99+